JP7430573B2 - Bipolar power storage device - Google Patents

Description

The present disclosure relates to a bipolar power storage device.

Bipolar secondary batteries are known as batteries installed in hybrid electric vehicles, electric vehicles, etc. (see Patent Document 1). In this bipolar type secondary battery, a plurality of bipolar type battery stacks are stacked and electrically connected in series, and a current collector and an electrode tab for taking out the battery output are connected at both ends in the stacking direction. An adhesive portion is placed in between. In each bipolar battery stack, a plurality of bipolar electrodes are stacked with an electrolyte layer interposed therebetween. According to this secondary battery, since the current collector and the electrode tab are fixed by the adhesive part, even when used in an environment where vibrations are applied, there is no difference between the bipolar battery stack and the electrode tab. Misalignment can be suppressed, and deterioration in battery performance caused by misalignment can be prevented.

Japanese Patent Application Publication No. 2009-135079

By the way, in a bipolar power storage device having a plurality of stacked bipolar power storage modules, in order to improve the energy density or output density of the power storage device, a pair of restraint plates are provided at both ends of the stacked bipolar power storage modules in the stacking direction. It has been considered to arrange a plurality of bipolar power storage modules and pressurize (restrict) a plurality of bipolar power storage modules from the direction in which they are stacked by a pair of restraining plates. In order to apply a stable restraint load to the plurality of bipolar power storage modules arranged between the pair of restraint plates, for example, a metal restraint plate is used as the restraint plate. When using a metal restraining plate, a short circuit between the restraining plate and the electrode tabs (current collecting members) placed at both ends of the stacked bipolar energy storage modules in the stacking direction must be avoided. To prevent this, for example, an insulating plate made of insulating resin is arranged. However, the coefficient of static friction between an insulating plate made of an insulating resin and a metal current collector is the same as the coefficient of static friction between two metal plates such as a metal current collector and a metal current collector that are placed in contact with each other. It is small compared to the coefficient of static friction. Therefore, when an external force such as vibration is applied to a bipolar power storage device, misalignment is more likely to occur between the resin insulating plate and the metal current collecting member compared to the contact area between two metal plates. A problem occurs.

The present disclosure provides a bipolar power storage device in which the occurrence of misalignment between an insulating plate and a current collecting member that are arranged adjacent to a restraining plate is suppressed.

A bipolar power storage device according to one aspect of the present disclosure includes: a power storage module; a pair of restraint plates that apply a restraining load to the power storage module with the power storage module sandwiched therebetween in a stacking direction; and one restraint plate of the pair of restraint plates. and the electricity storage module and electrically connected to the electricity storage module, an insulating plate arranged between the one restraining plate and the electricity collection member, and the electricity collection member. An adhesive portion is provided between the member and the insulating plate, and connects the current collecting member and the insulating plate to each other.

According to the power storage device, the adhesive portion that adheres the insulating plate and the current collecting member to each other makes it difficult for the insulating plate and the current collecting member to be misaligned.

The insulating plate extends in a longitudinal direction that intersects the lamination direction and a transverse direction that intersects the lamination direction and the longitudinal direction, and the adhesive portion extends in the longitudinal direction. good. In this case, even if a large external force in the longitudinal direction is applied to the power storage device, misalignment between the insulating plate and the current collecting member is unlikely to occur.

The insulating plate is an injection molded product made of resin, and the insulating plate has a first main surface facing the one restraining plate and a second main surface opposite to the first main surface. The insulating plate has, on the first main surface, a plurality of hollowed out portions that are recessed from the first main surface, and a rib portion that stands upright so as to partition the neighboring hollowed out portions. You may. In this case, when a restraining load is applied in the stacking direction by the pair of restraining plates, the bonded portion can move into the sink. Adhesion between one of the restraining plates and the insulating plate can be maintained by the adhesive portion within the sink.

At least one of the one restraining plate and the insulating plate may have a positioning portion for positioning between the one restraining plate and the insulating plate. In this case, misalignment between one of the restraining plates and the insulating plate is unlikely to occur.

At least one of the current collecting member and the insulating plate may have a positioning portion for positioning between the current collecting member and the insulating plate. In this case, misalignment between the current collecting member and the insulating plate is unlikely to occur.

According to the present disclosure, it is possible to provide a bipolar power storage device in which the occurrence of misalignment between an insulating plate and a current collecting member that are arranged adjacent to a restraining plate is suppressed.

FIG. 1 is a schematic perspective view of a bipolar power storage device according to this embodiment. FIG. 2 is a cross-sectional view of the bipolar power storage device of FIG. 1. FIG. 3 is a top view of the restraining plate. FIG. 4 is a top view of the insulating plate and the adhesive portion. FIG. 5 is a side view of the insulating plate and the adhesive portion. FIG. 6 is a perspective view showing a convex portion provided on the first main surface of the insulating plate. FIG. 7 is a sectional view showing an insulating plate having a convex portion and a restraining plate having a concave portion that fits into the convex portion. FIG. 8 is a top view of the positive electrode current collector plate. FIG. 9 is a cross-sectional view showing the restraining plate, the insulating plate, the adhesive part, and the positive electrode current collector plate. FIG. 10 is a top view of an insulating plate and a bonding part according to a modified example.

Embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and redundant description will be omitted. In the drawings, an XYZ orthogonal coordinate system is shown as necessary.

FIG. 1 is a schematic perspective view of a bipolar power storage device according to this embodiment. FIG. 2 is a cross-sectional view of the bipolar power storage device of FIG. 1. Bipolar power storage device 10 (hereinafter simply referred to as power storage device 10) shown in FIGS. 1 and 2 is used as a battery for various vehicles such as forklifts, hybrid vehicles, and electric vehicles. The power storage device 10 includes a plurality of (three in this embodiment) power storage modules 12, but may include a single power storage module 12. The electricity storage module 12 includes a positive electrode formed by forming a positive electrode active material layer on the surface of a conductive current collector, a negative electrode formed by forming a negative electrode active material layer on the surface of the current collector, and an electrode between the positive electrode and the negative electrode. This is a bipolar battery having a power generation element including an electrolyte layer in which an electrolyte is held in a separator disposed in a separator, and a bipolar battery having a plurality of stacked bipolar electrodes. The power storage module 12 is, for example, a secondary battery such as a nickel metal hydride secondary battery or a lithium ion secondary battery. In the following description, a bipolar type nickel-metal hydride secondary battery will be exemplified.

A plurality of power storage modules 12 may be stacked with conductive plates 14 interposed therebetween. The conductive plate 14 is made of, for example, a highly conductive metal plate. Hereinafter, when simply referred to as "the stacking direction", the "stacking direction" means the stacking direction (Z-axis direction) of the plurality of power storage modules 12. When viewed from the stacking direction, the power storage module 12 and the conductive plate 14 are each formed into, for example, a rectangular shape.

In the present embodiment, each power storage module 12 includes an electrode stack in which a plurality of bipolar electrodes and a plurality of separators holding an electrolyte are alternately stacked, and a separator arranged at one end in the stacking direction of the electrode stack. A negative terminal electrode, and a positive terminal electrode disposed at the other end of the electrode stack in the stacking direction with a separator interposed therebetween. A separator is placed between adjacent bipolar electrodes. Each of the plurality of bipolar electrodes includes a current collector, a positive electrode active material layer provided on one surface of the current collector, and a negative electrode active material layer provided on the other surface of the current collector. In other words, each bipolar electrode has a structure in which a positive electrode active material layer, a current collector, and a negative electrode active material layer are stacked in this order. A pair of bipolar electrodes adjacent in the stacking direction are stacked such that the positive electrode active material layer of one bipolar electrode faces the negative electrode active material layer of the other bipolar electrode with a separator in between. In other words, between a pair of bipolar electrodes adjacent in the stacking direction, a positive electrode having a current collector and a positive electrode active material layer, a negative electrode having a current collector and a negative electrode active material layer, and a positive electrode. A power generation element is configured including an electrolyte layer in which an electrolyte is held in a separator disposed between negative electrodes. The direction in which the plurality of bipolar electrodes and separators in each power storage module 12 are stacked is the same as the direction in which the plurality of power storage modules 12 in the power storage device 10 are stacked. The negative terminal electrode includes a current collector and a negative active material layer provided on one surface of the current collector. The negative terminal electrode is arranged such that the surface on which the negative active material layer is formed faces the positive active material layer of the bipolar electrode adjacent in the stacking direction with the separator in between. The positive terminal electrode includes a current collector and a positive active material layer provided on one surface of the current collector. The positive terminal electrode is arranged such that the surface on which the positive active material layer is formed faces the negative active material layer of the bipolar electrode adjacent in the stacking direction with the separator in between. A separator and an electrolytic solution are housed in internal spaces formed between electrodes adjacent in the stacking direction, and each internal space is sealed by a sealing part. Exposed portions where the current collector is exposed from the sealing portion are provided on both end faces of the power storage module 12 in the stacking direction. A conductive plate 14 or a current collecting plate to be described later is placed in contact with this exposed portion, and the electricity storage module 12 is electrically connected to the conductive plate 14 or the current collecting plate.

Among the plurality of stacked power storage modules 12, a positive electrode current collector plate 24 as a current collecting member is arranged on the outside of the power storage module 12 located at one end in the stacking direction (lower side in the Z direction in FIG. 2). . The positive electrode current collector plate 24 is made of, for example, a highly conductive metal plate, and is electrically connected to the power storage module 12 located at one end. The positive current collector plate 24 has a first main surface 24a and a second main surface 24b opposite to the first main surface 24a. The second main surface 24b faces the power storage module 12 located at one end. The positive electrode current collector plate 24 is, for example, formed in a rectangular shape when viewed from the stacking direction. Among the plurality of stacked power storage modules 12, a negative electrode current collector plate 26 as a current collecting member is arranged on the outside (upper side in the Z direction in FIG. 2) of the power storage module 12 located at the other end in the stacking direction. . The negative electrode current collector plate 26 is made of, for example, a highly conductive metal plate, and is electrically connected to the power storage module 12 located at the other end. The negative electrode current collector plate 26 has a first main surface 26a and a second main surface 26b opposite to the first main surface 26a. The second main surface 26b faces the power storage module 12 located at the other end. The negative electrode current collector plate 26 is, for example, formed in a rectangular shape when viewed from the stacking direction. The thickness of each of the positive electrode current collector plate 24 and the negative electrode current collector plate 26 is, for example, 5 mm or less. Conductive plate 14 is electrically connected to adjacent power storage modules 12 . Thereby, the plurality of power storage modules 12 are connected in series in the stacking direction. The positive electrode current collector plate 24 is provided with a positive electrode terminal that protrudes in a direction (for example, the Y-axis direction) that intersects the stacking direction. The positive electrode terminal may be integrally molded with the positive current collector plate 24, or may be a separately configured terminal member attached to the positive current collector plate 24. The negative electrode current collector plate 26 is provided with a negative electrode terminal that protrudes in the same direction as the positive electrode terminal. The negative electrode terminal may be integrally molded with the negative electrode current collector plate 26, or may be a separately configured terminal member attached to the negative electrode current collector plate 26. Power storage device 10 is charged and discharged via these positive and negative terminals.

The conductive plate 14 can also function as a heat sink for dissipating heat generated in the power storage module 12. For example, by providing a plurality of cooling channels 14a in the conductive plate 14 and flowing a cooling medium (e.g., gas such as air) through the plurality of cooling channels 14a, the electricity storage module 12 that generates heat can be efficiently cooled. can do. The plurality of cooling channels 14a are each configured as a through hole extending parallel to each other inside the conductive plate 14, and extend, for example, in a direction (Y-axis direction) intersecting the stacking direction. Each cooling channel 14a may extend in the X-axis direction. In this embodiment, the size of the conductive plate 14 as viewed from the stacking direction is smaller than the power storage module 12, but the size of the conductive plate 14 may be the same size as the power storage module 12, or it may be larger than the power storage module 12. It may be the size.

Power storage device 10 includes a restraining member 16 that restrains a plurality of stacked power storage modules 12, a plurality of conductive plates 14, a positive current collector plate 24, and a negative current collector plate 26 in the stacking direction. The restraint member 16 includes a pair of restraint plates 17 and 18 and a plurality of connecting members 19 that connect the restraint plates 17 and 18 to each other. The restraining plate 17 and the restraining plate 18 may be connected by a single connecting member 19. A pair of restraint plates 17 and 18 sandwich the plurality of power storage modules 12 in the stacking direction. The restraining plates 17 and 18 apply a restraining load to each power storage module 12 in the stacking direction. A plurality of connecting members 19 are connected to the edges of each restraining plate 17, 18.

The restraint plate 17 has a first main surface 17a and a second main surface 17b opposite to the first main surface 17a. A plurality of stacked power storage modules 12 are provided on the second main surface 17b side of the restraining plate 17. The first main surface 17a of the restraining plate 17 serves as the outer surface of the power storage device 10. The restraint plate 18 has a first main surface 18a and a second main surface 18b opposite to the first main surface 18a. A plurality of stacked power storage modules 12 are provided on the second main surface 18b side of the restraining plate 18. The first main surface 18a of the restraint plate 18 is the outer surface of the power storage device 10. The second main surface 17b of the restraint plate 17 and the second main surface 18b of the restraint plate 18 face each other in the stacking direction. The restraint plate 17 and the restraint plate 18 are formed into a rectangular shape when viewed from the stacking direction. Each of the restraining plates 17 and 18 is made of, for example, iron or metal so that a uniform restraining load can be applied to each part of the power storage module 12 sandwiched therebetween in the in-plane direction (X-axis direction in FIG. 2). Constructed from a highly rigid metal material such as aluminum.

The restraint plate 17 is provided with a plurality of through holes H1 that penetrate the restraint plate 17 in the stacking direction. The restraint plate 18 is provided with a plurality of through holes H2 that penetrate the restraint plate 18 in the stacking direction. Each of the plurality of connecting members 19 has a bolt 19a including a shaft extending in the stacking direction and a nut 19b screwed onto the bolt 19a. The shaft portion of the bolt 19a is inserted into each of the through holes H1 and H2. The head of the bolt 19a is arranged on the first main surface 17a of the restraint plate 17, and the threaded tip of the bolt 19a projects from the first main surface 18a of the restraint plate 18. A nut 19b is screwed onto the threaded end of the bolt 19a. The nut 19b is arranged on the first main surface 18a of the restraint plate 18.

An insulating plate 22 made of, for example, an insulating resin is disposed between the restraint plate 17 and the negative electrode current collector plate 26 in order to prevent a short circuit between the two members. An insulating plate 22 made of, for example, an insulating resin is arranged between the restraint plate 18 and the positive electrode current collector plate 24 in order to prevent short circuits between the two members. The insulating plate 22 includes, for example, resin such as polypropylene. The insulating plate 22 is, for example, an injection molded product. The insulating plates 22 arranged adjacent to the restraining plates 17 and 18 are formed, for example, in a rectangular shape when viewed from the stacking direction. The size of the insulating plate 22 is larger than the conductive plate 14 when viewed from the stacking direction. The insulating plate 22 has a first main surface 22a facing each of the restraining plates 17 and 18, and a second main surface 22b opposite to the first main surface 22a.

The power storage device 10 includes an adhesive portion 23 that connects the positive current collector plate 24 or the negative current collector plate 26 and the insulating plate 22 to each other. The adhesive portion 23 is arranged between the positive current collector plate 24 or the negative current collector plate 26 and the insulating plate 22 . The adhesive portion 23 includes, for example, a sealing material such as modified silicone or an adhesive. The thickness of the adhesive portion 23 in the lamination direction is, for example, 1 mm or less. The adhesive portion 23 is arranged between the positive current collector plate 24 or the negative current collector plate 26 and the insulating plate 22 . In this embodiment, the adhesive portion 23 is not provided so as to cover the entire surface of the insulating plate 22, so the second main surface 22b of the insulating plate 22 is connected to the first main surface of the positive electrode current collector plate 24 via the adhesive portion 23. The main surface 24a or the first main surface 26a of the negative electrode current collector plate 26 and the first main surface 24a of the positive electrode current collector plate 24 or the first main surface of the negative electrode current collector plate 26 without using the adhesive part 23. 26a.

The second main surface 17b of the restraint plate 17 is abutted against the negative electrode current collector plate 26 via the insulating plate 22 and the adhesive part 23, and the second main surface 18b of the restraint plate 18 is abutted against the insulating plate 22 and the adhesive part 23. It is abutted against the positive electrode current collector plate 24 through it. In this state, the restraining plates 17 and 18 are connected to each other by the connecting member 19. As a result, the insulating plate 22, the negative current collector plate 26, the positive current collector plate 24, the conductive plate 14, and the power storage module 12 are sandwiched and formed into a unit, and a restraining load is applied in the stacking direction.

Although the restraining plate 17 has the same structure as the restraining plate 18, the restraining plate 18 will be explained below as an example. Hereinafter, the restraining plate 18, the insulating plate 22, the adhesive portion 23, and the positive current collector plate 24 will be explained in detail with reference to FIGS. 3 to 9.

As shown in FIG. 3, the restraining plate 18 has a plurality of engaging portions 32 that engage with the plurality of connecting members 19, respectively. In this embodiment, a plurality of (for example, five) engaging portions 32 are arranged, for example, at equal intervals along each edge extending in the longitudinal direction (Y-axis direction) of the restraining plate 18. Each engaging portion 32 is provided with a through hole H2.

The restraint plate 18 has a plurality of rib parts 38 and a plurality of thin parts 39. The rib portion 38 sandwiched between the thin portions 39 is provided in a desired portion of the second main surface 18b of the restraining plate 18 by providing a thin portion 39 formed by cutting out the thickness so as to be recessed in a concave shape from the second main surface 18b. is formed. The plurality of rib portions 38 include a plurality of rib portions 38 extending in the X-axis direction, a plurality of rib portions 38 extending in the Y-axis direction, and a plurality of rib portions 38 extending in the diagonal direction intersecting both the X-axis direction and the Y-axis direction. A plurality of extending rib portions 38 are included. Each rib portion 38 extending diagonally connects the two engaging portions 32 to each other. Each of the plurality of thin parts 39 is defined by a plurality of rib parts 38. In the stacking direction, the thickness of each thin portion 39 is thinner than the thickness of each rib portion 38 and the thickness of each engaging portion 32. In this embodiment, the minimum thickness of each rib portion 38 is 15 mm or more and 25 mm or less. The minimum thickness of each thin portion 39 is 2 mm or more and 7 mm or less. The minimum thickness of each engaging portion 32 is greater than 7 mm and less than or equal to 20 mm.

The restraining plate 18 may have a plurality of (for example, six) positioning parts 18p for positioning between the restraining plate 18 and the insulating plate 22. In this embodiment, each positioning portion 18p is a recess having the same depth as the thin portion 39.

As shown in FIG. 4, the insulating plate 22 extends in a longitudinal direction (Y-axis direction) that intersects the lamination direction and in a transverse direction (X-axis direction) that intersects the lamination direction and the longitudinal direction. . The adhesive portion 23 extends in the longitudinal direction of the insulating plate 22. The insulating plate 22 has edges 22e along the widthwise direction at both longitudinal ends, and a center portion 22d disposed between the edges 22e in the lengthwise direction. In the longitudinal direction, the length of each edge 22e may be 1/3 or less of the length of the insulating plate 22. The adhesive portion 23 is arranged at the center portion 22d and each edge portion 22e. In this embodiment, the plurality of adhesive parts 23 are arranged at intervals in the lateral direction of the insulating plate 22. Each adhesive portion 23 extends in the longitudinal direction of the insulating plate 22 from one edge 22e through the center portion 22d to the other edge 22e.

As shown in FIGS. 4 and 5, the insulating plate 22 has a plate-shaped portion 22s having a first main surface 22a and a second main surface 22b. The second main surface 22b of the plate-shaped portion 22s corresponds to a restraint area that applies a restraint load to the power storage module 12. The ratio of the area of the second main surface 22b where the adhesive portion 23 is provided is determined depending on the restraint load, and is, for example, 70% or more.

The insulating plate 22 may have a plurality of (for example, six) positioning parts 22p for positioning between the restraining plate 18 and the insulating plate 22. In this embodiment, each positioning part 22p is a protrusion that fits into each positioning part 18p. Each positioning portion 22p is provided on the first main surface 22a. A plurality of positioning parts 22p are arranged along each edge extending in the longitudinal direction of the rectangular first main surface 22a. In addition, when each positioning part 18p of the restraint plate 18 is a protrusion, each positioning part 22p may be a recess that fits into each positioning part 18p.

As shown in FIGS. 6 and 7, each positioning portion 22p is, for example, a crushing rib. Each positioning portion 22p has a first rib 22p1 and a second rib 22p2 that are spaced apart from each other. When the first rib 22p1 and the second rib 22p2 are press-fitted into the positioning part 18p, which is a recess, as shown in FIG. 7, they are deformed so as to approach each other by being pressed by the positioning part 18p. As a result, the insulating plate 22 is positioned on the restraining plate 18.

As shown in FIGS. 4 and 5, the insulating plate 22 may have a positioning portion 22q for positioning between the positive electrode current collector plate 24 and the insulating plate 22. In this embodiment, the insulating plate 22 has positioning portions 22q at positions corresponding to corners of the restraining area of the insulating plate 22. Each positioning portion 22q is, for example, a protrusion. Each positioning portion 22q is provided on the second main surface 22b of the insulating plate 22. In addition to the positioning parts 22q provided at two of the four corners of the rectangular restraint area, another positioning part 22r may be provided at one of the remaining two corners. good. The positioning portion 22r is, for example, a protrusion.

As shown in FIG. 8, the positive electrode current collector plate 24 may have a positioning portion 24q for positioning between the positive electrode current collector plate 24 and the insulating plate 22. In this embodiment, the positive electrode current collector plate 24 has positioning portions 24q at positions corresponding to the positioning portions 22q of the insulating plate 22, respectively. Each positioning portion 24q is, for example, a notch or a depression formed to fit with the positioning portion 22q. In addition to the positioning parts 24q provided at two of the four corners of the rectangular restraint area, another positioning part 24r may be provided at one of the remaining two corners. good. The positioning portion 24r is, for example, a notch or a depression formed to fit with the positioning portion 22r. Each of the positioning parts 24q and 24r may be a projection, and each of the positioning parts 22q and 22r may be a notch or a recess that fits into the positioning parts 24q and 24r.

As shown in FIG. 9, the insulating plate 22 may have a plurality of rib portions 22u on the first main surface 22a so as to correspond to the rib portions 38 of the restraint plate 18. On the side of the first principal surface 22a of the insulating plate 22, a hollowed portion is provided at a desired portion so as to be hollowed out in a concave shape from the first principal surface 22a, so that adjacent hollowed portions are separated. A rib portion 22u is formed. That is, the rib portion 22u is a thicker portion of the insulating plate 22. By providing the rib portion 22u on the first main surface 22a of the insulating plate 22, a slight sink mark 22v (recess) is generated on the second main surface 22b of the insulating plate 22 at a position corresponding to the rib portion 22u. Since an adhesive portion 23 containing a sealant or adhesive is provided between the insulating plate 22 and the positive current collector plate 24, the sink 22v of the insulating plate 22 is filled with the sealant or adhesive. Become.

According to the power storage device 10 described above, the adhesive portion 23 that adheres the insulating plate 22 and the positive electrode current collector plate 24 to each other prevents the deviation between the insulating plate 22 and the positive electrode current collector plate 24 (the deviation in the direction crossing the stacking direction). ) is unlikely to occur. Similarly, the adhesive portion 23 that adheres the insulating plate 22 and the negative current collector plate 26 to each other makes it difficult for the insulating plate 22 and the negative current collector plate 26 to be misaligned. Therefore, even if an external force such as vibration is applied to power storage device 10, the above-mentioned deviation is unlikely to occur. Therefore, interference and short circuit between members due to misalignment can be suppressed. Furthermore, the warpage of the positive electrode current collector plate 24 and the negative electrode current collector plate 26 is corrected by the adhesive portion 23.

If the adhesive portion 23 extends in the longitudinal direction of the insulating plate 22, even if a large external force in the longitudinal direction is applied to the power storage device 10, the gap between the insulating plate 22 and the positive electrode current collector plate 24 will be avoided. Also, misalignment between the insulating plate 22 and the negative electrode current collector plate 26 is unlikely to occur.

When the insulating plate 22 has the rib portion 22u, when a restraining load is applied in the stacking direction by the pair of restraining plates 17 and 18, the adhesive portion 23 can move into the sink 22v. Adhesion between each restraint plate 17, 18 and the insulating plate 22 can be maintained by the adhesive portion 23 in the sink 22v.

When the restraining plate 18 has the positioning part 18p and the insulating plate 22 has the positioning part 22p, displacement between the restraining plate 18 and the insulating plate 22 is unlikely to occur. When the restraining plate 17 has a positioning part similar to the positioning part 18p and the insulating plate 22 has a positioning part 22p, misalignment between the restraining plate 17 and the insulating plate 22 is unlikely to occur. Moreover, each of the restraining plates 17 and 18 and the insulating plate 22 can be made into a unit.

When the insulating plate 22 has the positioning parts 22q and 22r, and the positive electrode current collector plate 24 has the positioning parts 24q and 24r, misalignment between the positive electrode current collector plate 24 and the insulating plate 22 is unlikely to occur. When the negative electrode current collector plate 26 has positioning parts similar to the positioning parts 24q and 24r, and the insulating plate 22 has the positioning parts 22q and 22r, misalignment between the negative electrode current collector plate 26 and the insulating plate 22 is unlikely to occur. . Further, the positive current collector plate 24 or the negative current collector plate 26 and the insulating plate 22 can be made into a unit.

Power storage device 10 may be manufactured as follows. First, the insulating plate 22 is placed on the second main surface 18b of the restraining plate 18. At this time, the positioning portion 22p of the insulating plate 22 is aligned with the positioning portion 18p of the restraining plate 18. Next, after applying the material for the adhesive part 23 onto the second main surface 22b of the insulating plate 22 using, for example, a dispenser, the positioning part 24q of the positive electrode current collector plate 24 is aligned with the positioning part 22q of the insulating plate 22. . When the positive electrode current collector plate 24 has the positioning part 24r and the insulating plate 22 has the positioning part 22r, the positioning part 24r may be aligned with the positioning part 22r. For example, first, after aligning the positioning portion 24r of the positive electrode current collector plate 24 with the positioning portion 22r of the insulating plate 22, the positive electrode current collector plate 24 is rotated about the positioning portions 22r, 24r, and the positive electrode current collector plate 24 is The positioning portion 24q is aligned with the positioning portion 22q of the insulating plate 22. Next, by pressing the positive electrode current collector plate 24 against the insulating plate 22, the material of the adhesive portion 23 is spread out. Thereby, the positive electrode current collector plate 24 and the insulating plate 22 are connected by the adhesive portion 23. Therefore, since the warpage of the positive electrode current collector plate 24 is corrected, the positioning accuracy between the positive electrode current collector plate 24 and the insulating plate 22 is improved.

Similarly, the insulating plate 22 is placed on the second main surface 17b of the restraining plate 17, and after applying the material for the adhesive portion 23, the negative electrode current collector plate 26 is pressed against the insulating plate 22. Thereby, the negative electrode current collector plate 26 and the insulating plate 22 are connected by the adhesive portion 23. Therefore, since the warpage of the negative electrode current collector plate 26 is corrected, the positioning accuracy between the negative electrode current collector plate 26 and the insulating plate 22 is improved.

After the power storage module 12 and the conductive plate 14 are stacked on the positive current collector plate 24, the unit including the restraint plate 17, the insulating plate 22, the adhesive part 23, and the negative current collector plate 26 is placed so that the negative current collector plate 26 faces downward. Then, turn it upside down and place it on the electricity storage module 12. When the unit is reversed, the adhesive portion 23 can prevent the negative electrode current collector plate 26 from falling. Thereafter, the restraining plates 17 and 18 are connected to each other using a plurality of connecting members 19.

FIG. 10 is a top view of an insulating plate and a bonding part according to a modified example. The adhesive part 123 shown in FIG. 10 has the same configuration as the adhesive part 23 except that it has a frame shape when viewed from the stacking direction. The adhesive portion 123 has, for example, a rectangular ring shape when viewed from the stacking direction. The adhesive portion 123 extends in the longitudinal direction and the lateral direction of the insulating plate 22. The adhesive portion 123 has a pair of long sides 123a extending longitudinally from one edge 22e through the center 22d to the other edge 22e on the second main surface 22b of the insulating plate 22; The edge 22e has a pair of short sides 123b extending in the lateral direction. The adhesive part 123 does not need to have the pair of long sides 123a.

The same effects as those of the above-described power storage device 10 can also be obtained in the power storage device including the adhesive portion 123 shown in FIG. 10 . Furthermore, even if a large external force is applied in any direction on the second main surface 22b (XY plane) of the insulating plate 22, the deviation between the insulating plate 22 and the positive current collector plate 24 and the Misalignment with the negative electrode current collector plate 26 is unlikely to occur.

Although the preferred embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above embodiments.

For example, in the present embodiment, the restraining plate 18 and the insulating plate 22 have the positioning part 18p and the positioning part 22p, respectively, but only one of the restraining plate 18 and the insulating plate 22 may have the positioning part. good. For example, if the insulating plate 22 does not have the positioning part 22p, the entire insulating plate 22 may fit into the positioning part (recess) of the restraining plate 18. Further, when the restraining plate 18 does not have the positioning part 18p, the entire restraining plate 18 may fit into the positioning part 22p (indentation) of the insulating plate 22.

Further, in this embodiment, the insulating plate 22 and the positive electrode current collector plate 24 each have the positioning parts 22q, 22r and the positioning parts 24q, 24r, but only one of the insulating plate 22 and the positive electrode current collector plate 24 has the positioning parts 22q, 22r and 24q, 24r. may have a positioning part. Similarly, only one of the insulating plate 22 and the negative current collector plate 26 may have a positioning portion. For example, when the insulating plate 22 does not have the positioning parts 22q and 22r, the entire insulating plate 22 may fit into the positioning part (indentation) of the positive current collector plate 24 or the negative current collector plate 26. In addition, if the positive current collector plate 24 or the negative current collector plate 26 does not have a positioning part, the entire positive current collector plate 24 or negative current collector plate 26 fits into the positioning part (indentation) of the insulating plate 22. Good too.

DESCRIPTION OF SYMBOLS 10... Bipolar power storage device, 12... Energy storage module, 17, 18... Restriction plate, 18p, 22p, 22q, 22r, 24q, 24r... Positioning part, 22... Insulating plate, 22a... First principal surface, 22b... Second Main surface, 22u... Rib part, 23, 123... Adhesive part, 24... Positive electrode current collector plate (current collector member), 26... Negative electrode current collector plate (current collector member).

Claims (5)

A power storage module,
a pair of restraint plates that sandwich the power storage module in a stacking direction and apply a restraint load to the power storage module;
a current collecting member disposed between one of the pair of restraint plates and the power storage module and electrically connected to the power storage module;
an insulating plate disposed between the one restraining plate and the current collecting member;
an adhesive part disposed between the current collecting member and the insulating plate and connecting the current collecting member and the insulating plate to each other;
Equipped with
In the bipolar power storage device , the insulating plate is an injection molded product made of resin . The insulating plate extends in a longitudinal direction that intersects the lamination direction and a transverse direction that intersects the lamination direction and the longitudinal direction,
The bipolar power storage device according to claim 1, wherein the adhesive portion extends in the longitudinal direction. The insulating plate has a first main surface facing the one restraining plate, and a second main surface opposite to the first main surface,
The insulating plate has, on the first main surface, a plurality of hollowed out parts that are recessed from the first main surface, and a rib part that stands upright so as to partition the neighboring hollowed out parts. Item 2. The bipolar power storage device according to item 1 or 2. The bipolar according to any one of claims 1 to 3, wherein at least one of the one restraining plate and the insulating plate has a positioning portion for positioning between the one restraining plate and the insulating plate. Type electricity storage device. The bipolar type power storage according to any one of claims 1 to 4, wherein at least one of the current collecting member and the insulating plate has a positioning portion for positioning between the current collecting member and the insulating plate. Device.

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